Rice finding 2620

Source evidence and comparison details for the Rice profile.

A.A. et al. 2008

Market rice (type not separated) · Dimethylarsinic acid (DMA) · 14 market rice samples (788 white) in the database, excluding field survey samples; field survey n per Table 3.5; speciation n=45.

Selected finding and reference

20 µg/kg (mean)Mean.

14 market rice samples (788 white) in the database, excluding field survey samples; field survey n per Table 3.5; speciation n=45. Basis: unspecified (market rice as purchased; Aberdeen database tables state no dry/fresh basis).

Minimum printed as '<0.05' mg/kg (a censored value with a 0.05 mg/kg bound); not imputed.

HMI baseline position

Moderate · HMI uncooked-grain DMA reference · 4 sampling families. Mean as reported: 20 µg/kg. HMI median 58.6; Q1 20; Q3 100 µg/kg. 4 families. Not a safety grade.

Low is below Q1; Moderate includes Q1 through Q3; High is above Q3. Reporting bounds must give the same category throughout.

This is an external comparison; the finding does not set the reference.

Sensitivity to weighting

Equal subgroup weight within each family: Moderate. The position is unchanged under this alternative. This check does not address all sampling, rounding or analytical uncertainty.

Sensitivity to source selection

These checks show dependence on each sampling family; they are not confidence intervals.

Reference, contributing evidence and methods

Collection period

Collection date unreported

No year-by-year sample register is reconstructed from this summary.

Geographic scope

purchased Bangladesh

Purchase or reporting market; growing origin not identified.

Sampling, analysis and reporting limits

Total arsenic per Williams et al. procedures (not described in this report) with NIST 1568a rice flour CRM; speciation by HPLC-ICP-MS after TFA extraction (Figure 3.4 caption; inorganic = arsenate + arsenite).

Minimum printed as '<0.05' mg/kg (a censored value with a 0.05 mg/kg bound); not imputed.

Source inconsistency noted (does not affect this value): minimum printed as '<0.05' while the maximum is 0.05 and the average 0.02; the censoring bound (0.05) is not below the detected values, so the minimum is only bounded at <=0.05.

Shared samples and study overlap

Subgroup rows, statistics of the same subgroup and the study total share samples; they are not independent results.

Each table row describes a food/analyte result. Repeated rows do not add independent samples or datasets. No cross-study trend is calculated in this comparison mode.

Reported values, conversion and source locator
Source statisticOriginal resultDisplayed unit conversion
meanaverage 0.02mg/kg x 1000

Table 3.7, p.21.

No moisture, cooking-yield or species conversion is applied to the original finding above. Any basis conversion used for its HMI comparison is stated separately with the numerical target.

Open the primary publication · HMI source record

Reference and scope

HMI uncooked-grain DMA reference · 4 sampling families. Uncooked grain as analysed (native or unstated moisture), µg/kg. Distribution of subgroup median concentration values.

Reference (µg/kg)Q1MedianQ3
Primary HMI reference2058.6100
Alternative weighting2058.6100

11 reference units; 4 sampling families. Counts describe evidence units, not independent studies or certainty.

Contributing familyReference unitsWeight
WHO GEMS/Food525%
Liu et al. 2022225%
Sim et al. 2024125%
Zavala et al. 2008325%

Methods

HMI pools subgroup medians from every compatible rice sampling family in the evidence ledger for this analyte, material and basis: published subgroup medians, medians HMI calculates from printed per-sample values and WHO GEMS/Food region-by-year medians (random sampling only). Each family has equal total weight; subgroups have equal weight within a family. Non-detects stay as zero-to-limit intervals, so quartiles carry lower and upper bounds. Means, ranges and maxima never enter as observations. Dry-weight, native-moisture and cooked results are kept in separate references; no moisture conversion is assumed.

Inverse weighted empirical CDF; midpoint at exact cumulative-weight boundaries. At least four reference units and a definitely positive Q1–Q3 spread are required. This is a display eligibility rule, not statistical validation.

Limitations

An evidence-library reference, not a probability sample of the world rice market. Sampling families differ in frame (retail, farm, contaminated sites, monitoring) and period; GEMS/Food regions are reporting regions, not growing origins. Many submissions are non-detects with differing limits, which widens the bounds. A position is descriptive concentration, not a safety or compliance judgment.

Admitted source families

Reference version and interpretation

Frozen evidence selection: 2026-10-22. Method: hmi-pooled-reference-v2.

hmi-pooled-reference-v2:rice-native-DMA:72c9b8f9eec4

The reference is computed by HMI from admitted evidence, not copied from a study baseline. It describes the evidence currently in this scope; it is not a worldwide or current-lot benchmark. Source, year and region filters do not change it. Different HMI scopes are not one common ranking.